WattsyHow this PSU calculator works
It adds up the maximum power each part can draw under full load, using the CPU's max turbo power and the GPU's rated board power. Then it recommends a power supply that runs at roughly 60–75% of its capacity at that load. That leaves headroom for brief power spikes, keeps the fan quieter, and sits near the PSU's most efficient range.
Real-world gaming usually draws less than the max load shown, since the CPU and GPU rarely peak at the same moment. Sizing for the peak is the safe choice.
Common builds
| Build | Typical PSU |
|---|---|
| Ryzen 5 / Core i5 + RTX 5060 or RX 9060 XT | 550–650 W |
| Ryzen 7 / Core i7 + RTX 5070 or RX 9070 | 650–750 W |
| Ryzen 7 9800X3D + RTX 5070 Ti or RX 9070 XT | 750–850 W |
| High-end CPU + RTX 5080 | 850–1000 W |
| High-end CPU + RTX 5090 | 1000–1200 W |
Frequently asked questions
What wattage power supply do I need?
Add your parts above. Most gaming PCs with a mid-range graphics card need a 650–850 W power supply. Builds with an RTX 5080 or 5090 usually need 850 W to 1200 W.
Is a bigger power supply bad?
No. A PC only draws the power it needs, so an oversized PSU won't waste much energy. It just costs more up front. An undersized PSU is the real problem, since it can cause crashes or shutdowns under load.
Does PSU efficiency rating matter?
80 Plus Gold is a good target for most builds. Higher ratings waste less power as heat, but the savings on your electricity bill are usually small.
Do I need an ATX 3.1 power supply?
For recent high-end NVIDIA cards that use the 12V-2x6 (16-pin) connector, an ATX 3.1 PSU with a native cable is the cleanest and safest option. These standards are also designed to handle the short power spikes modern GPUs produce.